Nanobubbles: tiny oxygen boosters for dying seas and lakes

An ozone nanobubbler kept the Lincoln Memorial Reflecting Pool clear by oxidizing algae, illustrating a potential for nanobubbles to deliver oxygen to bottom sediments in lakes and seas to curb eutrophication and internal nutrient release; interfacial oxygen nanobubbles attached to porous materials could reduce energy use and target the sediment layer, but energy demands, potential ecological effects, and ongoing runoff remain major challenges, as Baltic Sea projects show the approach’s promise and limits.